Polishing machine



- May 10, 194.9.

POLISHING MACHINE Filed July 10, 1948 3 Sheets-Sheet l m l N MN: U @N s 5 mm w kw ww mm m w 6 Jr mwuwwufim anja BJ Umwfi-II-I I Maiy #0, 1949. v E. c. LINDSAY ET AL POLISHING MACHINE '5 Sheets-Sheet 2 Filed July 10, 1948 M 6 SVJH W R e r ma N n mu M4 m L d e 6 v r n Mw m Q2 y 9' E. c. LINDSAY ET AL 2,469,735

POLISHING MACHINE Filed July 10, 1948 5 Sheets-Sheet 3 INVENTORS Er/Ward (LL/ndsayand if i 1 Eugene L.,4nde/"5on 4] i 4120 A4440, MQJa,

Patented May 10, 1949 UNITED STATES TENT OFFICE gene L. Anderson,

Standard Steel Spring Company,

Coraopolis, Pa, assignors to Coraopolis,

Pa., a corporation of Pennsylvania Application July 10, 1948, Serial No. 37,988

9 Claims.

This invention relates to an abrasive belt polishing machine comprising a driving roll, a work roll and a tension roll, all mounted on a frame and having an abrasive belt passing around the rolls. While the invention is applicable to polishing a wide Variety of articles, it will be described as applied to the polishing of automobile bumpers. The bumpers are conveyed to a position in front of the polishing machine by an endless conveyor and are then pressed by a workman against the work roll, the abrasive belt being driven continuously and being interposed between the work roll and the bumper. The workman moves the bumper while resting on the endless conveyor so as to polish different portions of the bumper.

In the accompanying drawings, which illustrate a preferred embodiment of my invention:

Figure 1 is a rear longitudinal elevation;

Figure 2 is a plan view;

Figure 3 is an end elevation taken from the right-hand side of Figure 1;

Figure 4 is a transverse section taken on the line IV-IV of Figure 1;

Figure 5 is a section taken on the line V-V of Figure 2;

Figure 6 is a section taken on the line VI-VI of Figure 2;

Figure 7 is an enlarged View of a portion of the device shown in Figure 6, the bearings being shown in section and a portion of the work roll being broken away; and

Figure 8 is a section on the line VIIIVIII of Figure 1.

Referring more particularly to the accompanying drawings, the workpiece 22 to be polished, for example, an automobile bumper, is brought to the polishing machine and supported in position in front of the polishing machine by an endless conveyor 3, the conveyor including vertical supports 4, rollers 5 and a fabric conveyor belt 6.

The frame of the polishing machine is made of tubular members I, 8 and =9. The tubular members 1 and 8 are connected together at their left-hand ends as viewed in Figures 1 and 6. The left-hand ends of the tubular members 8 and 9 are connected together by an angle iron II, and intermediate their ends these tubular members are connected by two plates l2. The right-hand ends of the tubular members "I, 8

and 9 are connected to a plate l3 which supports the motor M for driving a driving roll I5. A work roll it and a tension roll ll also are supported by the frame. and an abrasive belt l8 passes around the driving roll, the work roll and the tension roll.

A plate It, shown in Figures 1 and 2, is secured to the plate l3 and a large gear 2% is secured to the plate It by short posts 2!. A stub shaft 22 connected to the gear 20 is rotatably mounted in a bearing 23 provided in a bracket 2 having a collar 25 fitting over a post 2d, the collar being secured to the post by bolts 2?. The post is slidable in a guideway 28 formed in a base 29. The post can he slid in its guideway 28 toward or away from the Work supporting conveyor 3. The collar 25 can be raised and lowered on the post so as to raise and lower the frame so as to adjust the work roll to the proper height with respect to the bumper bar 2 being polished.

Means is provided for rotating the frame constituted by the tubular members I, 8 and 9 so as to tilt the work roll it in order to polish the top 30 or either of the face portions 3! or 32 of the bumper. To provide for this tilting movement of the frame, the gear 2% meshes with a pinion 33 mounted on a shaft 35, the shaft having a worm wheel 35 secured to its other end, the worm wheel meshing with a worm 36 which is rotatable by means of a handle 3?. Rotation of the handle 3? causes the pinion 33 to rotate the large gear 20 which is rigidly secured to the frame, thereby tilting the whole frame, including the work roll It, to present it at the proper angle with respect to the workpiece being polished.

In prior known abrasive belt polishing machines there has been a tendency for the belt to slip off the Work roll when pressure is applied to the work roll by pressing the workpiece against it. This is particularly true where different portions of the workpiece have different curvatures because while a Work roll can be adjusted to conform to one curvature, it is difficult to have it conform to different curvatures of the workpiece, and these differences in curvature exert different actions on the belt, which is backed by the work roll, and oftentimes cause the abrasive belt to slip off the work roll. This tendency of the abrasive belt to slip off the work roll when a workpiece having different curvatures in its different portions is applied to the work roll, is overcome according to the present invention by mounting the work roll in the manner now to be described. The mounting for the work roll is shown more particularly in Figures 4-7. The work roll 16 is secured to a, shaft Mi, each end of the shaft being supported in a bearing 4!. A metal sleeve 42 having a collar 33 integral therewith is secured to each end of the shaft, and a resilient packing material 3 is interposed between the sleeve and the bearing. Accordingly, the shaft is resiliently mounted in the bearings by the resilient packing material so that the axis of the shaft can tilt out of its normal position to a limited extent in any plane so as to conform the work roll to the contour of the workpiece which is pressed against the abrasive belt.

In addition to resiliently mounting the shaft in the bearings M, as shown in Figure '7, the bearings 4| are independently and resiliently supported from the frame in such manner that the work roll shaft can tilt in one plane out of its normal position so as to conform the work roll to the contour of the workpiece being polished. This independent resilient mounting of each of the bearings 4| is shown more particularly in Figures 4-6. Each of the bearings 4| is supported by a bearing support 36 connected to the bearing by a bolt 41. Each of the bearing supports 46 is slidable independently of the other bearing support in a guide 48 secured to the frame. The guide 48 has a plate 19 welded to a bracket 59 which is welded at each end to one of the plates [2 as shown in Figure 5. The plate 49 forming a portion of the guide lies below the sliding bearing support 46. Two side strips 5| and two top strips 52 form the remainder of the guide. A bracket 53 is secured to the plate 52 forming a portion of the guide, and a bracket 54 is secured to the sliding bearing support 46. A rod 55 passes through an opening in each of the brackets. A spring 56 surrounding the rod is interposed between the two brackets 53 and 54 and a spring 51 surrounding the rod is interposed between the bracket 54 and a nut '58 on the end of the rod. A nut 59 also is provided on the rod.

It will be seen that the bracket 53 is fixed to the guide and since the guide is fixed to the frame, the bracket 53 is fixed relative to the frame. The bearing support 46 and the bracket 54, however, are movable relative to the frame so that the work roll l5 can be moved toward or away from the workpiece. The springs 56 and 51 act in opposition to each other with respect to their tendency to move the work roll toward or away from the workpiece. The spring 56 urges the work roll away from the workpiece, whereas the spring 51 urges the work roll toward the workpiece. Tightening the nut 58 on the rod 55 compresses the spring 5'! and increases its biasing force. Likewise, tightening the nut 59 on the rod increases the biasing force of the spring 56. The spring 56 preferably is stronger than the spring 5.1.

By the arrangement shown in Figure 6, in which each end of the shaft 46 is mounted in a bearing 4| which is independently and. resiliently supported from the frame, the work roil shaft 410 can tilt in one plane out of its normal position so as to conform the work roll to the contour of the workpiece, thereby aiding in keeping the ;belt on the Work roll. The tracking of the belt is further aided by the arrangement shown in Figure 7, wherein each end of the work roll shaft is resiliently mounted in its bearing.

The means for mounting the tension roll I! so as to aid in replacing an abrasive belt, adjust ing the tension of the belt, and centering the belt on the work roll by movement of the tension roll is shown in Figure 8 and at the left-hand portions of Figures 1 and 2. The shaft 62 of the tension roll I! is mounted in a slide 63 which is slidable in a guide 64. The slide has a tang portion 65 extending from its left-hand end. A ratchet rod 66 has one end 61 extending through an opening in the tang portion 65, this end portion being surrounded by a spring 68 retained in place by a nut 69. The other end 10 of the ratchet rod is provided with teeth cooperating with a pawl H connected to a bracket 12 which is secured to the guide 64. A lever 13 is pivoted at M to the bracket 12 and is pivoted at 15 to the ratchet rod 86. A brace 16 reinforces the bracket i2. Movement of the lever 13 from the dotted to the full line position shown in Figure 1 moves the ratchet rod 66 to the left against the tension of the spring 68 and moves the slide 653 and tension roll ii to the left to maintain the tension of the abrasive belt. A belt may be changed by releasing the pawl H and moving the slide 63 to the right.

The guide 4 is hinged to the frame by a hinge pin H passing through openings in the guide and openings in hinge parts 18 secured to the angle iron II which is welded to the tubular members 8 and 9. Because of this hinged connection between the mounting for the ,tension roll and the frame, the tension roll I! can be tilted out of its normal position about the hinge H as an axis so as to turn the face of the tension roll to align the belt on the work roll 15 as desired. The tension roll H is held in ad.- justed position by a bolt and nut 19 connecting a bracket secured to the frame with a bracket {5| secured to the guide 64.

In the use of the apparatus the workman presses the bumper 2 against the abrasive belt is which is backed by the work roll 16, the bumper being moved lengthwise relative to the work roll while the bumper is supported on the moving conveyor 3. A series of polishing machines are provided, each having its work roll adjusted at a different angle in order to polish different transverse portions of the bumper. The work roll it not only is resiliently mounted as a whole, but each end of the work roll shaft .40 is mounted in a bearing 3! which is independently and resiliently supported from the frame so that the work roll shaft can tilt in one plane out of its normal position so as to conform the work roll to the contour of the workpiece, thereby aiding in keeping the belt on the work roll. This action is further increased by the provision of the resilient mounting of each end of the work roll shaft in its individual bearing.

The invention is not limited to the preferred embodiment, which has been given merely for purposes of illustration, but may be otherwise embodied or practiced within the scope of the following claims.

We claim:

1. In an abrasive belt polishing mas hi le, .a frame, a work roll having an abrasive ,beltpassing around. it and mounted ,on a shaft, a bearing supportin ea h end or the sha t, each bea n being independently and resiliently supported from the frame, whereby the work r01 shaft ca tilt in one plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt.

2. In an abrasive belt polishing machine, a frame, a work roll having an abrasive belt passing around it and mounted on a shaft, a bearing supporting each end of the shaft, a bearing support connected to each bearing, two bearing support guides connected to said frame, each bearing support being independently slidable in its guide, and biasing means associated with each bearing support and guide for limiting movement of each bearing support in its guide, whereby the work roll shaft can tilt in one plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt.

3. In an abrasive belt polishing machine, a frame, a work roll having an abrasive belt passing around it and mounted on a shaft, a bearing supporting each end of the shaft, a bearing support connected to each bearing, two bearing support guides connected to said frame, each bearing support being independently slidable in its guide, a first spring associated with each guide and bearing support and urging the bearing support away from the abrasive belt, and a second spring associated with each guide and bearing support and urging the bearing support toward the abrasive belt to tighten it, whereby the work roll shaft can tilt in one plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt.

4. In an abrasive belt polishing machine, a frame, a Work roll having an abrasive belt passing around it and mounted on a shaft, a bearing supporting each end of the shaft, a bearing support connected to each bearing, two bearing support guides connected to said frame, each bearing support being independently slidable in its guide, a first bracket secured to each of said bearing supports, a second bracket secured to each of said guides, a rod passing through each pair of brackets constituted by a first and second bracket, a first spring on the rod between each pair of brackets, a second spring on each rod on the opposite side of said first bracket from said first spring, and a nut on each rod for compressing each spring of a pair of springs, whereby the work roll shaft can tilt in one plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt.

5. In an abrasive belt polishing machine, a frame, a work roll having an abrasive belt passing around it and mounted on a shaft, a bearing resiliently supporting each end of the shaft, each bearing being independently and resiliently supported from the frame, whereby the work roll shaft can tilt in one plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt.

6. In an abrasive belt polishing machine, a frame, a work roll having an abrasive belt passing around it and mounted on a shaft, a sleeve fitting over and secured to the shaft adjacent each end thereof, a bearing surrounding but spaced from each sleeve, and resilient packing material between each bearing and sleeve, each bearing being independently and resiliently supported from the frame, whereby the work roll shaft can tilt in any plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt.

'7. In an abrasive belt polishing machine, a frame, a work roll having an abrasive belt pass ing around it and mounted on a shaft, a sleeve fitted over and secured to the shaft adjacent each end thereof, a collar fixed to each sleeve, a bearing surrounding but spaced from each sleeve, and resilient packing material between each bearing and sleeve, each bearing being independently and resiliently supported from the frame, whereby the work roll shaft can tilt in any plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt.

8. In an abrasive belt polishing machine, a frame, a driving roll and a work roll and a tension roll supported by the frame, an abrasive belt passing around said rolls, a shaft on which the work roll is mounted, a bearing supporting each end of the shaft, each bearing being independently and resiliently supported from the frame, whereby the work roll shaft can tilt in one plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt, a slide in which the tension roll is mounted, a guide receiving the slide, and means for maintaining the tension roll in adjusted position, said guide being hinged to the frame so that the angular position of the tension roll can be changed to align the belt on the work roll.

9. In an abrasive belt polishing machine, a frame, a driving roll and a Work roll and a tension roll supported by the frame, an abrasive belt passing around said rolls, a shaft on which the work roll is mounted, a bearing resiliently supporting each end of the shaft, each bearing being independently and resiliently supported frcm the frame, whereby the work roll shaft can tilt in any plane out of its normal position so as to conform the work roll to the contour of a workpiece pressed against the abrasive belt, a slide in which the tension roll is mounted, a guide receiving the slide, and means for maintaining the tension roll in adjusted position, said guide being hinged to the frame so that the angular position of the tension roll can be changed to align the belt on the work roll.

EDWARD C. LINDSAY. EUGENE L. ANDERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,045,945 Carney Dec. 3, 1912 2,089,808 Ocenasek Aug. 10, 1937 2,106,082 Carlson Jan. 18, 1938 2,199,069 Fowler Apr. 30, 1940 2,272,273 Parker Feb. 10, 1942 2,334,960 Roth et al. Nov. 23, 1948 

